Classifying Angles Worksheet Worksheet for 3rd - 6th Grade ... - Free Printable

Explanation:
We need to classify each angle as ACUTE, RIGHT, OBTUSE, or STRAIGHT.

Let’s recall what each means:
- Acute angle: less than 90° (sharp, narrow angle)
- Right angle: exactly 90° (like the corner of a square — often marked with a small square symbol)
- Obtuse angle: more than 90° but less than 180° (wide, but not flat)
- Straight angle: exactly 180° (a straight line — two rays pointing in opposite directions)

Now, go through each angle one by one:

1. First row, left: Looks like a wide angle, clearly more than 90° but less than 180° → OBTUSE
2. First row, middle: Very narrow, much less than 90° → ACUTE
3. First row, right: Open angle, looks wider than 90°, less than 180° → OBTUSE

4. Second row, left: Two lines forming a “V” shape, fairly narrow — less than 90° → ACUTE
5. Second row, middle: Has the little square mark — that means it’s exactly 90° → RIGHT
6. Second row, right: A straight horizontal line — two rays in opposite directions → STRAIGHT

7. Third row, left: Has the square mark again → RIGHT
8. Third row, middle: Narrow “V”, definitely less than 90° → ACUTE
9. Third row, right: Straight line (slanted, but still a straight line) → STRAIGHT

Let me double-check:
- Acute: angles #2, #4, #8 → 3 angles
- Right: #5, #7 → 2 angles
- Obtuse: #1, #3 → 2 angles
- Straight: #6, #9 → 2 angles
That adds up to 9 angles — matches the worksheet.

Final Answer:
OBTUSE, ACUTE, OBTUSE, ACUTE, RIGHT, STRAIGHT, RIGHT, ACUTE, STRAIGHT